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Tech Talk

Tech Talk


About Clarity

  • Generally speaking, if anything can be seen with the naked eye, the stone is graded with one of the Imperfect grades. Nevertheless, on bigger stones such as 1.50 carat and up, some visible flaws will not always drop the stone's grade, as you have to take the size of the stone into consideration.


  • The one and two sub-grades (VS2, SI1,SI2 etc) generally indicate the placement of any inclusions. ONE usually means that the majority of the inclusion(s) are on the outside edge of the diamond while a TWO grade refer to the majority of the inclusion(s) being underneath the table or in the centre of the diamond.

    BUT BE WARNED as the completely opposite can also true! A diamond that has a large inclusion on the outside edge (in relation to the stone's size) could be down-graded to a TWO - and a table inclusion which is very small (in relation to the stone's size) could be upgraded to a ONE.

About Colour

  • Small, subtle differences in colour can make a substantial difference in value. Although increasing shades of yellow reduce the value of a diamond, they do not necessarily reduce its beauty. If a diamond is well cut, refraction and dispersion will often disguise certain degrees of colouration.


  • A diamond's colour can only be determined by holding the " Unknown" Diamond next to a diamond with a known colour and comparing the two.


  • D-E-F-G are the top four colour grades. They carry a dollar premium that increases as the colour get closer to D. But remember -just because the stone is a good colour doesn't mean it is a good diamond. It's just that the crystal is of good colour. H colour is a fine all-round colour with I colours being used very well in a Solitaire style ring. After the five colour grades, the price can drop considerably but the stones will start showing a distinctive yellow tint, even to an untrained eye.

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